Six sailors set out on the 40,000km around-the-world Ultim Challenge from France on Sunday, hoping to complete one of the sport's "biggest challenges" inside 50 days.
Under bright winter sunshine in the Brittany port of Brest, the first such race on super-powerful but relatively fragile trimarans got underway.
The Edmond de Rotshchild, helmed by Charles Caudrelier, was the early evening leader with an advantage of a few nautical miles.
Caudrelier, Tom Laperche (SVR Lazartigue), Thomas Coville (Sodebo), Armel Le Cleac'h (Banque Populaire), Anthony Marchand (Actual) and Eric Peron (Adagio) were the six men to cross the starting line in their 32-metre-long crafts.
In mild conditions for a Breton Sunday in January, the six giant multihulls began to fly on their foils, the side appendages which allow the boats to rise above the water to reach breakneck speeds.
The fastest could take around 50 days to complete the 21,600 nautical miles of this race, rounding the Cape of Good Hope (South Africa), Cape Leeuwin (Australia) and Cape Horn (Chile) in the process.
Their departure from Brest was emotional and tearful.
"Obviously there is emotion, but we will have to quickly switch to racing mode at the start," said Marchand, 38, shedding a tear when his team gathered around the mast of his Ultim to welcome him.
"We're going for an extraordinary race, but it will really be extraordinary when we finish it."
Sailing out in the morning light towards the starting line out of Brest harbour, the six men were accompanied by their entourages until the last moment.
- 'Very beautiful story' -
Some crew departed the craft by diving into the frigid sea just before cannon fire marked the start of the race.
"Everything comes together for a very beautiful story, I grew up here in Finistere, I learned to sail here. It makes me happy to see everyone gathered to encourage us. It's up to me to succeed in my mission from now on," explained Le Cleac'h, who is setting off on his fourth around the world trip.
However, it's his first in a trimaran after three Vendee Globes, including victory in 2017.
Completing a solo around-the-world trip in a trimaran is a rare accomplishment.
Trimarans are faster but experts regard the craft as much more fragile and riskier than a monohull.
Only seven sailors have achieved the feat, including just four who have done it non-stop.
The most recent was Francois Gabart, who set the record for the enterprise in 2017 after 42 days spent at sea.
On Sunday, he was on the SVR Lazartigue to accompany Laperche who, at 26, has now set off on his first circumnavigation.
"There's impatience, stress, concentration, emotion, a little bit of everything... I'm going to make the most of it," said Laperche.
"The objective is to cross the finish line with a boat in good condition. It is one of the biggest challenges of all of our careers," added Caudrelier.